PLEASE PROCEED AT YOUR OWN RISK, THE FOLLOWING PAGE IS FOR INFORMATION PURPOSES ONLY, YOU SHOULD ONLY USE THESE TECHNIQUES IF YOU ARE COMPETENT TO DO SO. WE ACCEPT NO RESPONSIBILITY FOR ANY DAMAGE CAUSED BY FOLLOWING THESE INSTRUCTIONS.
* Warning *
Never use a heat gun on laminated glass, such as windshields and certain Mercedes back glass.
The only way to avoid using strips on a compound curve window is to use the heat shrinking method. This is an advanced technique and best left to a professional. It involves using a heat gun to shrink the excess film along the grain (toward the factory edge) and smoothing it out with a rolled up paper towel or a hard card.
The best way to learn it is to watch one being done. Keep in mind that the film will only shrink properly toward the factory straight edge.
Wet Shrinking:
On an oversized piece of tint laying on soapy water on the outside of the back window with the liner still in place facing up, squeegee a horizontal anchor onto the film to bring all the excess film into finger shapes on the top and bottom of the window.
Pass the heat gun over a finger quickly, just until you see the film react, smooth that area flat with a rolled up paper towel, then do the fingers that pop up on either side of the one you just smoothed flat and so on. After the film is all flat repeat the procedure with a hard card instead of a paper towel. Cut the film to shape and repeat step 2 (hard card smoothing) as some fingers will pop up after it's cut to shape. To lay it in, roll it up onto a drum stick, reverse the liner and roll it out onto the prepared inner surface. Squeegee it out, etc.
Unheated finger on left, heated
finger ready to smooth on the right.
Squeegee a horizontal anchor to
bring the excess film to the top and bottom.
You must use a heat gun on high setting, a hair dryer will not get hot enough! You are only shrinking the finger itself, just pass the heat gun over the finger quickly until you see it distort slightly, then smooth it out. If you spend just a moment too long over the finger it will burn, or shrink unevenly. The trick is not to crease the film when you smooth it, so the first time use a rolled up paper towel to smooth the finger down to keep the film wet against the glass, otherwise larger fingers will bind and crease if you use the hard card first, repeat the process with a grey hard card.
VERY IMPORTANT, the film will only shrink properly if the fingers are aligned with the grain of the film. As you unroll film from side to side the proper grain direction is up and down, i.e. If you have a window 45" wide horizontally and 18" vertically, using a 20" roll, the fingers need to point up and down toward the straight factory cut edge. Fingers always need to be moved toward the factory edge. Squeegee a horizontal anchor onto the glass to anchor the middle and sides moving all the excess to vertical fingers. Heat shrinking is very challenging, I recommend you watch one being done just to be clear on what I'm saying.
Dry shrinking
Using baby powder wiped onto the glass instead of water will allow you to heat shrink large areas instead of fingers one at a time. This is known as dry shrinking and is very difficult to master, but will allow you to do most windows in one piece. The following series of pictures shows me doing a dry shrink on a Toyota Camry rear window.
When anchoring the film just let it go where it wants, just make sure all horizontal fingers are moved to the vertical, usually most of the excess will be toward the sides.
